Start by clarifying requirements and scale, then present a high-level architecture with core APIs and data model. Dive into the email delivery pipeline, covering capacity, scheduling, rate limiting, failure handling, observability, compliance, multi-region, and cost, and finish with a concrete failure scenario.
Pro tip: Emphasize idempotency and exactly-once semantics for email delivery, and discuss how to handle partial failures gracefully with retries and dead-letter queues. Also, mention the importance of monitoring and alerting on delivery rates and latency to quickly detect issues.
Ask questions to understand the event types, participant volume, email content, latency requirements, and compliance needs. Confirm the 1 million concurrent events and email delivery expectations.
Outline the core components: event ingestion API, message queue, email service, and data stores. Define key APIs for event creation and participant registration.
Describe the data model for events, participants, and email jobs. Explain the email delivery pipeline: queuing, batching, rate limiting, and integration with email providers.
Discuss capacity estimates, scheduling, rate limiting, failure handling (retries, DLQ), observability (metrics, logging), compliance (GDPR, CAN-SPAM), multi-region availability, and cost optimization.
Choose a concrete failure (e.g., email provider outage) and explain detection, mitigation, and recovery steps, including fallback providers and retry strategies.
AI-generated suggestions, not part of the candidate's original notes. May be inaccurate — verify before relying on them.